Caption: Purple coneflower. View of the flowers of the purple coneflower, also known as the hedge coneflower, Echinacea purpurea. This is a native plant of the Eastern and Northern USA and was used by the North American Indians to treat burns and wounds. The leaves and roots are said to contain an immunostimulant, an agent that causes the formation of the body's antibodies. Until the 1950's, the purple coneflower was commonly used as an anti-infection agent in the USA.